Market research has shown that “softness” is a property of paper-based consumer products, such as paper towels, paper napkins, bathroom tissue, and the like, as well as some non-paper-based consumer products, which is important to consumers in selecting and determining the quality and desirability of such products. Therefore, it is advantageous to be able to demonstrate a consumer product's softness to the consumer, as a way of making the product more desirable.
Consumer perception of softness is complex, composed of multiple vectors such as surface smoothness, fuzziness, scratchiness, cottony, flexibility, cushy, etc. There is no single test that quantifies overall softness. There are existing methods for scientifically quantifying and demonstrating certain components of softness. One such method for testing a given product's cushy softness is to use a compressive testing machine, such as the Vantage Compression Tester, available from Thwing-Albert Instrument Company of West Berlin, N.J. Such a machine will apply an increasing force to the surface of a paper towel or other test sample placed between two metal surfaces, and measure the caliper of the sheet as the amount of force applied to the sheet is increased. Caliper is the distance between the stationary platform on which the sample is placed and the foot used by the instrument to apply force to the sample.
The amount of each successive weight applied and the corresponding amount of compression of the towel (as measured by the test equipment's caliper) may be plotted on a graph, as illustrated in FIG. 1. The data points shown in FIG. 1 are plotted with the compressive pressure applied to the test sample (in grams/sq. in.) plotted linearly on the horizontal (x) axis, and the caliper reading (in mils) plotted linearly on the vertical (y) axis, with a smaller caliper reading indicating a narrower gap between the two metal testing surfaces. This data may be used to calculate the compressibility of the material tested by re-plotting the data with the caliper reading plotted linearly on the vertical (y) axis and the weight applied plotted logarithmically on the horizontal (x) axis, as shown in FIG. 2. A linear regression of the data plotted in FIG. 2 is performed to reduce the data to a straight line. The magnitude of the slope of that line is indicative of the compressibility of the material. A high value of compressibility, as determined by this test process, is highly analogous to the more subjective “softness” quality of paper towels and other consumer products. Such softness has been identified as a desirable property in paper products during consumer product testing.
One significant drawback of using compressive testing equipment is that the results of scientific compressibility testing, while perhaps easily understood by one who is literate in the art of materials testing or in mathematics, may not be understood by the average consumer, who may not readily recognize how the quantitative results of scientific testing relate to the more subjective “soft” feeling of an actual paper towel or other consumer product. Therefore, a more dynamic method of demonstrating the softness of a consumer product, using easily understood methods and familiar test materials, is desirable. Ideally, this method would use the paper towel product in a manner easily understood and related to by consumers. Such a method could be filmed or photographed and then used in advertisements, or it could be carried out in the direct presence of consumers, as a live demonstration in a store or other public location.